<html>
<head>
	<meta charset="utf-8">
	<meta name="viewport" content="width=device-width, initial-scale=1">
	<title></title>
	<style type="text/css">
		 
	</style>
</head>
<body>
 	<!DOCTYPE html>
<html>
<head>
	<meta charset="utf-8">
	<meta name="viewport" content="width=device-width, initial-scale=1">
	<title></title>
	<style type="text/css">
		 .box{
		 	width: 1200px;
		 	height: 600px;
		 	background: aqua;
		 	display: flex;
		 }
		 .box div{
		 	width: 200px;
		 	height: 100px;
		 	margin: 10px;
		 	background: pink;
/*		 	flex: 1;*/
		 }
		 .box .item2{
		 	background:green;
		/*	flex 分配父元素的剩余空间,给子元素设置之后,主轴方向的宽/高 大小 看flex设置的大小	 	*/
		/*	占剩余空间的(1+4=5)5分之一	*/
		 	flex: 1;
		 }
		 .box .item3{
		 	background: blue;
		 	/*	占剩余空间的(1+4=5)5分之4	*/
		 	flex: 4;
		 }
	</style>
</head>
<body>
	<div class="box">
		<div class="item1">1</div>
		<div class="item2">2</div>
		<div class="item3">3</div>
	</div>
</body>
</html>
</body>
</html>